----------------------- MS-DOS v6.22 Help: DBLSPACE ------------------------
<Notes>                                                              <Index>
Configures drives that were compressed by using DoubleSpace, the integrated
compression that was included with MS-DOS 6 and MS-DOS 6.2.
Note:  MS-DOS 6.22 does not include DoubleSpace compression. Instead, MS-DOS
       6.22 includes DriveSpace compression, which appears similar to
       DoubleSpace but which stores compressed information in a different
If you currently use DoubleSpace, you can continue to do so with MS-DOS
6.22. For more information about using DoubleSpace with MS-DOS 6.22, see
If you currently use DoubleSpace and want to use DriveSpace instead, you can
convert your system to DriveSpace. For more information, see "Converting
from DoubleSpace to DriveSpace" in <Notes>.
If you do not currently use DoubleSpace and want to compress your drives,
use DriveSpace. To do this, type DRVSPACE at the command prompt. For more
information, see <DRVSPACE>, or see "Freeing Disk Space by Using DriveSpace"
in your Microsoft MS-DOS User's Guide or Microsoft MS-DOS User's Guide
When you issue the DBLSPACE command by itself, the DoubleSpace program
starts. You can use this program to create and manage DoubleSpace compressed
If you add switches or parameters to the DBLSPACE command, MS-DOS carries
out the requested task without starting the DoubleSpace program. The command
syntax differs from task to task.
Note:  The switches and parameters for the DBLSPACE command are identical to
       those of the DRVSPACE command. MS-DOS 6.22 Help describes only the
       command syntax for DRVSPACE. If you use DoubleSpace instead, refer to
       the Help for the corresponding DRVSPACE command, and just type
       DBLSPACE instead of DRVSPACE when issuing the command.
You can use the DBLSPACE command to perform the following tasks:
*  Compress a hard disk drive or floppy disk. For more information, see

*  Create a new compressed drive in the free space on an existing drive. For
   more information, see <DRVSPACE /CREATE>.

*  Defragment a compressed drive. For more information, see

*  Delete a compressed drive. For more information, see <DRVSPACE /DELETE>.

*  Format a compressed drive. For more information, see <DRVSPACE /FORMAT>.

*  Display information about a compressed drive. For more information, see

*  Display a list of the drives on your computer. The list includes
   compressed and uncompressed hard disk drives, floppy disk drives, and
   other removable-media drives. It does not include network drives. For
   more information, see <DRVSPACE /LIST>.

*  Mount a compressed volume file (CVF). When DoubleSpace mounts a CVF, it
   assigns it a drive letter; you can then use the files that CVF contains.
   For more information, see <DRVSPACE /MOUNT>.

*  Change the estimated compression ratio of a compressed drive. For more
   information, see <DRVSPACE /RATIO>.

*  Change the size of a compressed drive. For more information, see

*  Uncompress a compressed drive. For more information, see

*  Unmount a compressed drive. For more information, see

*  Change the settings in your DRVSPACE.INI file. For more information, see

Creating a startup floppy disk
To create a startup floppy disk if you are running DoubleSpace, use either
the SYS command or the FORMAT /S command. Each of these commands creates a
floppy disk that should in most cases be able to start your computer.
However, to make sure, you should also copy the DBLSPACE.BIN file from the
directory that contains your MS-DOS files to the root directory of the
startup floppy disk.
For more information about creating a startup floppy disk, see the <SYS> or
<FORMAT> commands.
Loading DBLSPACE.BIN into the HMA
If you are running DoubleSpace and you upgraded to MS-DOS 6.22 from MS-DOS
6.2, you can load a portion of DBLSPACE.BIN into the High Memory Area (HMA).
To do this, you must have an 80286 or higher computer with at least 1 MB of
memory and your CONFIG.SYS file must contain a DOS=HIGH command, a DEVICE
command for HIMEM.SYS, and a DEVICE command for DRVSPACE.SYS. (MS-DOS Setup
and DoubleSpace Setup normally add these commands to your CONFIG.SYS file.)
If you upgraded from MS-DOS 6.0, DBLSPACE.BIN cannot be loaded into the HMA;
in this case, you can save about 14K of memory by converting to DriveSpace,
which can load into the HMA. For more information about converting to
DriveSpace, see the following section.
Converting from DoubleSpace to DriveSpace
If you are running DoubleSpace, you can convert your DoubleSpace drives to
DriveSpace format. (If you purchased the U.S. version of the MS-DOS 6.22
Upgrade, you can obtain conversion by sending in the enclosed coupon; if you
purchased the MS-DOS 6.22 Step-Up or non-U.S. version of MS-DOS 6.22, your
version of MS-DOS 6.22 already includes conversion.)
Note:  Before converting, it's a good idea to back up the data on each
       DoubleSpace drive.
To convert your DoubleSpace drives, type DRVSPACE at the command prompt.
DriveSpace starts. To convert your drives, follow the instructions on your
screen. DriveSpace converts all mounted DoubleSpace drives to DriveSpace
format, and also converts your system to run DriveSpace instead of
Note:  The conversion process can take a long time, especially if your
       DoubleSpace drives contain a lot of data. You might want to plan to
       carry out the conversion process overnight.
For more information about converting to DriveSpace, see the README.TXT
Keeping DoubleSpace files after conversion
After conversion, do not delete any of your DoubleSpace program files,
especially the DBLSPACE.BIN file and the DRVSPACE.MR1 file. These files are
required in the following situations:
*  DriveSpace requires these files in order to convert any DoubleSpace
   volume files (for example, compressed floppy disks) that were not mounted
   during the initial conversion process.
*  ScanDisk requires these files to check and repair any unconverted
   DoubleSpace volume files.
*  MS-DOS 6.22 Backup for MS-DOS (MSBACKUP) requires these files to restore
   compressed backups created using the MS-DOS 6 or 6.2 Backup programs.
   (Most older backups are compressed backups, since those programs created
   compressed backups by default.)
Using DoubleSpace drives and floppy disks with DriveSpace
DriveSpace converts only DoubleSpace drives that were currently mounted
during the conversion process. As a result, after the conversion is
complete, you might still have some unconverted DoubleSpace floppy disks or
other unmounted DoubleSpace volume files. DriveSpace can still mount
unconverted DoubleSpace drives for read-only access; this means that you can
read but not change the information stored on that drive.
DriveSpace does not automatically mount DoubleSpace floppy disks; to mount
an unconverted DoubleSpace floppy disk, you must mount it yourself by using
the DRVSPACE /MOUNT command or by running DriveSpace and choosing the Mount
command from the Drive menu.
For DriveSpace to mount any DoubleSpace drive for full (read/write) access,
you must first convert the drive to DriveSpace format. To do this, run
DriveSpace, and then choose Convert DoubleSpace from the Tools menu.

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Last update: June 14, 2000 06:20 EST by -vjf-
Content © 1997 Microsoft Corporation
All else © 2000 Vernon J Frazee